Comparisons of hearing threshold changes in male workers with unilateral conductive hearing loss exposed to workplace noise: a retrospective cohort study for 8 years

Table 3 Comparisons of threshold changes between SNHL and CHL ear during follow-up period by noise level

	Noise level < 85 dBA (N = 53)									Noise level ≥ 85 dBA (N = 25)
	Difference of Air conduction			Difference of Bone conduction			Difference of Air-bone gap			Difference of Air conduction			Difference of Bone conduction			Difference of Air-bone gap
kHz	Mean^a	SD^d	p	Mean^b	SD^d	p	Mean^c	SD^d	p	Mean^a	SD^d	p	Mean^b	SD^d	p	Mean^c	SD^d	p
0.5	−0.9	8.9	0.469	−2.5	8.2	0.027	1.7	7.8	0.125	−0.6	5.8	0.633	1.8	22.7	0.702	−2.3	23.0	0.618
1	−0.6	10.5	0.695	−2.1	10.4	0.147	1.5	8.1	0.175	−1.9	8.5	0.280	−3.5	8.6	0.051	1.6	4.8	0.098
2	−0.8	10.3	0.578	−0.5	11.0	0.757	−0.3	6.9	0.737	−0.1	8.0	0.960	−1.8	8.2	0.270	1.8	6.7	0.202
3	1.0	10.5	0.477	1.9	8.9	0.131	−0.8	7.6	0.432	2.7	8.3	0.118	0.6	9.9	0.750	2.0	7.8	0.202
4	2.2	10.7	0.149	0.3	7.3	0.794	1.9	7.9	0.087	5.6	8.8	0.004	2.1	6.6	0.124	3.4	6.7	0.017
6	1.2	13.0	0.503	-	-	-	-	-	-	−0.4	13.7	0.896	-	-	-	-	-	-

p-value was calculated by paired t-test; ^aMean, difference of air conduction threshold (2013-2006) at SNHL ear vs. difference of air conduction threshold (2013-2006) at CHL ear; ^bMean, difference of bone conduction threshold (2013-2006) at SNHL ear vs. difference of bone conduction threshold (2013-2006) at CHL ear; ^cMean, average of air-bone gap; ^d SD standard deviation

ISSN: 2052-4374